/Engine/Source/Editor/UnrealEd/Public/FbxImporter.h
Make un-smooth faces work.
int32 number of points that added when process unsmooth faces
int32 DoUnSmoothVerts ( [FSkeletalMeshImportData](API\Runtime\Engine\Rendering\FSkeletalMeshImportData) & ImportData, bool bDuplicateUnSmoothWedges )